Using a data base derived from three generation family group sheets covering approximately 178,000 families within which one or more members experienced a vital event on the pioneer trail or in Utah, demographic studies are being conducted focusing primarily on the nineteenth century. The analysis of fertility levels and particularly their shift from natural fertility schedules to a controlled fertility schedule received primary emphasis at this time. Utilization of log-linear methods are being employed to disaggregate the effects of migration, religion, age of marriage, child spacing, and age of termination of childbearing and marriages, relative to fertility levels and change. Analysis of infant mortality rates and nuptiality patterns are now in process, along with more detailed studies of patterns of migration and characteristics of migrants associated with western frontier settlement. Development of new data base management techniques is also central to the project.